Glossary

Alexandrite

  • Colors: The finest alexandrites are a blue green in daylight and a purplish red under incandescent light. The greater the color change, the more rare (and valuable) the stone.
    Stones with a faint color change should be identified as chrysoberyl.
  • Source: Originally Russia, now Egypt, Brazil, Myanmar, Madagascar and other areas
  • Chemical: A variety of Chrysoberyl (Aluminum beryllium oxide) with chromium, which is responsible for the color change
  • Formation: Pegmatite dikes
  • Wear ability: Very good with a hardness of 8.5

Andalusite

  • Colors: Cobination of brown, green and yellowish to white
  • Source: Named for Andalusia, Spain but also found in Brazil, Sri Lanka, Russia, U.S., Canada and Africa.
  • Chemical: Aluminum silicate
  • Formation: Found mostly in gem gravels ; rarely found as crystals.
  • Wear ability: Good with a hardness of 7.5.

Apatite

  • Colors: Yellow, infrequently; Neon Blue, green and blue/green
  • Source: Numerous places around the world including Sri Lanka, India, Madagascar, U.S. and Mexico
  • Chemical: Calcium phosphate
  • Formation: Prismatic Crystals
  • Wear ability: Apatite is a 5 on the Mohs Scale which means that it is not a good stone to use in rings. With adequate care, it wears well when set in earrings or pendants. It is a beautiful stone and is well worth the effort needed to preserve it.
  • NOTE : AS WITH ALL FINE JEWELRY, PIECES SHOULD BE STORED SEPARATELY IN A SOFT POUCH OR A DESIGNATED JEWELRY LINED BOX OR DRAWER.
    Apatite should not be placed in an ultrasonic cleaner or steamer and ammonia based cleaning solutions should be avoided. Care requirements are similar to an opal.

Chrysoberyl

  • Colors: Honey, golden brown, rarely, red (in order to consider a red chrysoberyl an alexandrite it must have significant color changing properties). Chrysoberyl can be seen as faceted stones or the very exotic cat’s eye cabochons.
  • Source: Originally Russia, now Egypt, Brazil ,Sri Lanka, Tanzania and Zimbabwe and other locations, however; production is very limited making these stones quite rare.
  • Chemical: Aluminum Beryllium Oxide
  • Formation: Pegmatite dikes
  • Wear ability: Very good with a hardness of 8.5

Diamonds

Though the natural colored diamonds are extremely rare, diamonds in general must be included in any glossary as they are the mainstay of any jewelry piece.

  • Colors: Diamonds are most often colorless or with tints of brown or yellow. Red, green, blue and yellow diamonds can be found though they are quite rare. Treatments can produce these or additional colors. As long as the treatment is disclosed and is an “approved” treatment (one that is permanent), this is acceptable in the Gem world.
  • Source: In order of production, diamond mines are located in: Botswana, Russia, Canada, Australia and Brazil. At this time, there is still a monopoly in place vis a vis the De Beers Corporation and through the Diamond Trading Company. Of interest, so called “Blood” or “Conflict” Diamonds make up less than 5% of the diamond market.
  • Chemical: Diamonds are carbon! Nitrogen is present in some types which produces the brown and yellow colors; boran produces the blue color.
  • Formation: Cubic system; diamonds crystallized as far as 150 km deep in the earth up to 3 billion years ago. They were brought to the surface at an incredibly fast rate (in excess of 500 km/p/h) by kimberlite magma.
  • Wear ability: Excellent, as the hardness on the Mohs scale is 10. However, as with all fine gems, care must be taken in the treatment of these stones. Though diamonds are difficult to scratch (hardness) they may be subject to breaking (tenacity).

Diaspore (Zultanite)

  • Color: This is a color changing stone usually from green in daylight to brown in incandescent light.
  • Source: Turkey
  • Chemical: ALOOH (aluminum oxide hydroxide) with magnesium and/or Iron as an impurity
  • Formation: Metamorphosed limestones, chloritic schists and altered igneous rocks.
  • Wear ability: Good with a Moh’s hardness of 6.5-7

Emerald

  • Color: Green with various modifying colors including blue and yellow
  • Source: Columbia, Zambia, Brazil, India
  • Chemical: Aluminum beryllium silicate
  • Formation: Hydrothermal vents
  • Wear ability: Good, though care is required. It is a hard stone, 7.5, but has internal liquid filled fractures and inclusions.
  • FUN FACT: SOME OF THE INCLUSIONS IN AN EMERALD CAN ACTUALLY BE REMNANTS OF ANCIENT SALTWATER SEA THAT EXISTED WHERE THE EMERALD FORMED!

Garnet

  • Color: Many colors including red, brown, green and yellow
  • Source: Many sources throughout the world
  • Chemical: This is one of our isomorphous replacement groups. Garnets belong in the crystal system and are all silicates, they run from magnesium aluminum silicates to calcium chromium silicates.
  • Formation: Igneous rocks; usually dodecahedral crystals
  • Wear ability: Excellent.
  • Fun fact: Sine garnets are an isomorphous replacement group, there are many different types: Pyrope, Amandine, Spessartite, Grossular, Uvarovite, Demantoid, Tsavorite, Rhodolite, Hessonite and more.

Iolite

  • Color: Intense blue purple to colorless within the same stone
  • Source: Mainly Brazil, Sri Lanka, India
  • Chemical: Magnesium aluminum silicate
  • Formation: Igneous rocks and pegmatites
  • Wear ability: Good
  • Fun Fact: Look closely at an Iolite gem: it will appear dark blue or purple in one direction and colorless in another. There is nothing else like this in the gemstone world!

Quartz

  • Color: A wonderful array of colors from colorless to the amethyst purple to the green citrine to the pale blue-greeen of chalcedony.
  • Source: Virtually on every continent in the world
  • Chemical: Silicon Dioxide
  • Formation: Pegmatite dikes
  • Wear ability: Good

Red Beryl

  • Color: Red
  • Source: Utah, U.S.
  • Chemical: Aluminum beryllium silicate colored by manganese
  • Formation: Pegmatite dikes
  • Wear ability: Good
  • Fun Fact: This is a rare and hard to find stone! It is sometimes referred to as bixbite or red emerald.
    When we can find a good specimen, we will make a beautiful piece of jewelry to showcase this fabulous gemstone!

Rhodonite

  • Color: Red to pinkish red
  • Source: Sweden, U.s., Canada, Australia and South Africa
  • Chemical: Manganese Silicate
  • Formation: Igneous rocks
  • Wear ability: Fair as it is soft; however; in a pendant or earrings it does well. It’s uniqueness and beauty makes the extra care worthwhile.

Ruby

  • Color: Red! If it is more purple than red it should properly be categorized as a sapphire.
  • Source: Mogok, Myanmar(Burma), Thailand, Australia, Viet Nam and many other places. It should be noted that there is presently an embargo on Burmese Rubies.
  • Chemical: Aluminum oxide with chromium
  • Formation: Created when granite forming lava intrudes into limestone marble.
  • Wear ability: Excellent as ruby (corundum) is the second hardest gemstone on the Moh’s scale.
  • Fun Fact: Ruby can offer asterism (star ) and chatoyancy (cat’s eye) phenomena. One ray of light will allow you to visualize this phenomena.

Sapphire

  • Color: Every color but red!!
  • Source: Many sources including Mogok, Myanmar, Thailand, Australia, Tanzania
  • Chemical: Aluminum oxide with titanium and iron to produce the blue color. Pink is colored by chromium. Iron is the coloring agent for most yellows and greens.
  • Formation: granite forming lave intrudes into limestone marble.
  • Wearablility: Excellent, as mentioned above, corundum is the second hardest gemstone on the Moh’s scale.
  • Fun Fact: As with Ruby (also a corundum), sapphires can offer asterism (star) and chatoyancy(cat’s eye). As with Ruby, the star will be six rayed owing to the hexagonal shape of corundum. A four rayed star will not be a ruby or sapphire!

Sphene

  • Color: Wow! Greenish to greenish yellow, BUT, the dispersion (fire) of this gemstone makes it appear to offer every color of the rainbow.
  • Chemical: CaTiSio2; frequently called Titanite
  • Formation: Igneous rock
  • Wear ability: Due to its extreme dispersion it can be brittle so is best suited for earrings and pendants.
    However; it is well worth the extra care required as there is no other stone that displays this much color in a rainbow effect. A very rare stone!

Spinel

  • Color: Usually red, blue and yellow. Greens and blacks
    are possible.
  • Source: Mynamar, Afghanistan, Sri Lanka, Brazil and the U.S.
  • Chemical : Magnesium aluminum oxide
  • Formation: Igneous rock
  • Wear ability: Good. This is a beautiful stone that sparkles brilliantly and works well on its own as well as accent stones! Look for an upcoming fun fact about its history that confirms its beauty!

Sunstone

  • Color: Orange, brownish red, red
  • Source: Oregon is the largest source but it is also found in India, Canada and Russia.
  • Chemical: Sodium calcium aluminum silica
  • Formation: Igneous rock
  • Wear ability : Very Good. This stone is known for its Schiller effect which is an iridescence creating a lovely display of color.

Tanzanite

  • Colors: blue/purple, bluish green
  • Chemical: Calcium aluminum silicate. There are no synthetic tanzanites as the chemical formula is so complicated.
  • Source: Tanzania
  • Formation: Igneous Rock
  • Wear ability: Tanzanite can be brittle and is best suited for necklaces and earrings. It is a beautiful stone which offers two colors at the same time!

Topaz

  • Color: Many colors. The blue topaz is colorless that has been irradiated and heated..This color is stable. Imperial Topaz, in most markets, is used to describe any of the pink, red, champagne, peach and salmon. The GIA says that only the unheated variety of peach should be termed Imperial Topaz.
  • Source: Brazil, Australia, U.S., Zimbabwe, Nigeria
  • Chemical: Aluminum fluo silicate
  • Formation: Pegmatite Dikes
  • Wear ability: Very Good.

Tourmaline

  • Color: Many beautiful colors! Many are bi color and can have as many as seven colors within the same crystal!
  • Source: Brazil, U.S., Sri Lanka
  • Composition: A complicated formula containing aluminum borosilicates
  • Formation: Pegmatite dikes
  • Wear ability: Very Good. A beautiful gem that can be any color in the rainbow.

Taaffeite (pronounced tarfite)

  • Color: Lavender
  • Source: Sri Lanka
  • Composition: Beryllium magnesium aluminum oxide
  • Wear ability: Very good. This is a very rare stone primarily found in Sri Lanka. Not only is the rare gem beautiful, it is durable which is a rare combination in itself!

Zircon

  • Color: Reddish brown, the blue is heat treated and there is a very rare green (due to radiation)
  • Source: Mynamar, Vietnam, Australia
  • Composition: Zirconium silicate
  • Formation: Igneous rocks
  • Wear ability: Very good. Zircon has extreme doubling of the facet junctions and is a beautiful gem. Zircon is a natural gemstone and is not cubic zirconia (CZ) though zirconium is the basic building block for CZ.